Nightjars and Lightbugs

Nightjars are now returning to the Forestry Commission's Thetford Forest and are pairing up ready to start nesting. Thetford Forest Ringing Group members were out on Thursday night in order to catch these birds to understand more about their movements on migration and particularly in their wintering quarters, as surprising little is currently known about this species. A first catch of four birds was a marvellous start to this new BTO/Biotrack project, supported by Shoreham & District Ornithological Society.

Unlike the Cuckoo, previously reported, the Nightjar is too small to have a Satellite transmitter fitted. Geolocator tags are an excellent alternative but we have to catch the birds again next year to download the information on their movements. These tags, known as Lightbugs, collect data on day length and time, which is used to calculate the bird’s global position to within 100km, each day. These daily locations will help reveal migration routes and wintering locations within Africa.


Just when you thought a near perfect night couldn't get any better, one of the females was discovered to be already ringed, RP01170. She was originally caught on migration, 171km away at Icklesham, Sussex on 15 September 1999 and we had not seen her since she was caught in the forest in 2008.

RP01170 has now broken the previous British and Irish longevity record, which stood at 11 years and 10 days, by 257 days. Amazingly, Brian Cresswell who helped fit the Lightbug to RP01170, originally caught the previous oldest Nightjar, in Dorset, back in 1992! So, quite a privilege to have handled the two oldest Nightjars in Britain and Ireland.

Thanks to Brian Cresswell and Forestry Commission for their valuable help and to Kate Risely for the photo (Lee Barber on left and Brian Cresswell on right).

Stonechat off to the coast... again

Thetford Forest, on the Norfolk/Suffolk border has a variety of habitats of Special Scientific Importance including woodland and heathland, which supports some scarce bird species like Nightjar, Woodlark and Goshawk. A recent colonist to the forest has been the Stonechat, and Thetford Forest Ringing Group has been studying this species, monitoring its movements and demography since its arrival.

Stonechat started to breed about 7 or 8 years ago and increased to about 56 pairs. After the recent cold winters the number of pairs has decreased dramatically to about 20 pairs. Adults and chicks have been colour ringed as part of a Retrap Adults for Survival (RAS) project with the aim of finding out where they go during the winter and to monitor the dispersal of chicks.

Most of the birds move out of the forest in the winter, resulting in some interesting movements (blue pins) of birds to the milder coast. See map below.

We have just heard from Trevor Girling (North West Norfolk Ringing Group) that a colour ringed female Stonechat has been seen at Snettisham Country Park (green pin) on Thursday 24th March. This bird was ringed as a chick by John Secker (Thetford Forest Ringing Group) at Hockwold (red pin) on 07/06/2010 and amazingly Trevor was overseeing this bird being ringed!


View Stonechat Thetford Forest in a larger map

It looks like this bird has now set up home at Snettisham with an unringed male and its progress will be followed by the N W Norfolk Ringing Group. Stonechat don't usually travel very far but these sightings are providing vital information about their movements.